385 citations · 1.7k across the 46 of their papers we have counts for
15 papers · 1 filter
A natural model for curved inflation
Quentin Vigneron, Julien Larena
Inflationary models with a non-zero background curvature require additional hypothesis or parameters compared to flat inflation and the procedure to construct them cannot be as sim…
Gravitational lenses in arbitrary space-times
Pierre Fleury, Julien Larena, Jean-Philippe Uzan
The precision reached by current and forthcoming strong-lensing observations requires to accurately model various perturbations to the main deflector. Hitherto, theoretical models…
Weak gravitational lensing of finite beams
Pierre Fleury, Julien Larena, Jean-Philippe Uzan
The standard theory of weak gravitational lensing relies on the infinitesimal light beam approximation. In this context, images are distorted by convergence and shear, the respecti…
Quantum theory of the Generalised Uncertainty Principle
Jean-Philippe Bruneton, Julien Larena
We extend significantly previous works on the Hilbert space representations of the Generalized Uncertainty Principle (GUP) in 3+1 dimensions of the form wher…
The theory of stochastic cosmological lensing
Pierre Fleury, Julien Larena, Jean-Philippe Uzan
On the scale of the light beams subtended by small sources, e.g. supernovae, matter cannot be accurately described as a fluid, which questions the applicability of standard cosmic…
Some cosmological consequences of a breaking of the Einstein equivalence principle
A. Hees, O. Minazzoli, J. Larena
In this communication, we consider a wide class of extensions to General Relativity that break explicitly the Einstein Equivalence Principle by introducing a multiplicative couplin…
Gravitational entropy of local cosmic voids
Roberto A. Sussman, Julien Larena
We undertake a non-perturbative study of the evolution of the "gravitational entropy" proposed by Clifton, Ellis and Tavakol (CET) on local expanding cosmic CDM voids of $\sim 50-1…
Observables in theories with a varying fine structure constant
A. Hees, O. Minazzoli, J. Larena
We show how two seemingly different theories with a scalar multiplicative coupling to electrodynamics are actually two equivalent parametrisations of the same theory: despite some…
Gravitational entropies in LTB dust models
Roberto A Sussman, Julien Larena
We consider generic Lemaitre-Tolman-Bondi (LTB) dust models to probe the gravitational entropy proposals of Clifton, Ellis and Tavakol (CET) and of Hosoya and Buchert (HB). We also…
Observables in a lattice Universe
Jean-Philippe Bruneton, Julien Larena
We explore observables in a lattice Universe described by a recently found solution to Einstein field equations. This solution models a regular lattice of evenly distributed object…
Dynamics of a lattice Universe
Jean-Philippe Bruneton, Julien Larena
We find a solution to Einstein field equations for a regular toroidal lattice of size L with equal masses M at the centre of each cell; this solution is exact at order M/L. Such a…
A two-mass expanding exact space-time solution
Jean-Philippe Uzan, George F. R. Ellis, Julien Larena
In order to understand how locally static configurations around gravitationally bound bodies can be embedded in an expanding universe, we investigate the solutions of general relat…
Power-law cosmic expansion in f(R) gravity models
Naureen Goheer, Julien Larena, Peter K. S. Dunsby
We show that within the class of f(R) gravity theories, FLRW power-law perfect fluid solutions only exist for R^n gravity. This significantly restricts the set of exact cosmologica…
Spatially averaged cosmology in an arbitrary coordinate system
J. Larena
This paper presents a general averaging procedure for a set of observers which are tilted with respect to the cosmological matter fluid. After giving the full set of equations desc…
Correspondence between kinematical backreaction and scalar field cosmologies - the `morphon field'
Thomas Buchert, Julien Larena, Jean-Michel Alimi
Spatially averaged inhomogeneous cosmologies in classical general relativity can be written in the form of effective Friedmann equations with sources that include backreaction term…